Make improvements

- Document redbean's argon2 module
- Fix regressions in cthreads library
- Make testlib work better with threads
- Give the cthreads library lots of love
- Remove some of the stdio assembly code
- Implement getloadavg() across platforms
- Code size optimizations for errnos, etc.
- Only check for signals in main thread on Windows
- Make errnos for dup2 / dup3 consistent with posix

This change also fixes a bug in the argon2 module, where the NUL
terminator was being included in the hash encoded ascii string. This
shouldn't require any database migrations to folks who found this module
and productionized it, since the argon2 library treats it as a c string.

third_party/make/dup2.c

@@ -1,216 +0,0 @@
-/* Duplicate an open file descriptor to a specified file descriptor.
-
-   Copyright (C) 1999, 2004-2007, 2009-2020 Free Software Foundation, Inc.
-
-   This program is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
-
-/* written by Paul Eggert */
-
-#include "libc/calls/calls.h"
-#include "libc/errno.h"
-#include "third_party/make/config.h"
-/* clang-format off */
-
-#if HAVE_DUP2
-
-# undef dup2
-
-# if defined _WIN32 && ! defined __CYGWIN__
-
-#  if HAVE_MSVC_INVALID_PARAMETER_HANDLER
-static int
-dup2_nothrow (int fd, int desired_fd)
-{
-  int result;
-
-  TRY_MSVC_INVAL
-    {
-      result = dup2 (fd, desired_fd);
-    }
-  CATCH_MSVC_INVAL
-    {
-      errno = EBADF;
-      result = -1;
-    }
-  DONE_MSVC_INVAL;
-
-  return result;
-}
-#  else
-#   define dup2_nothrow dup2
-#  endif
-
-static int
-ms_windows_dup2 (int fd, int desired_fd)
-{
-  int result;
-
-  /* If fd is closed, mingw hangs on dup2 (fd, fd).  If fd is open,
-     dup2 (fd, fd) returns 0, but all further attempts to use fd in
-     future dup2 calls will hang.  */
-  if (fd == desired_fd)
-    {
-      if ((HANDLE) _get_osfhandle (fd) == INVALID_HANDLE_VALUE)
-        {
-          errno = EBADF;
-          return -1;
-        }
-      return fd;
-    }
-
-  /* Wine 1.0.1 return 0 when desired_fd is negative but not -1:
-     https://bugs.winehq.org/show_bug.cgi?id=21289 */
-  if (desired_fd < 0)
-    {
-      errno = EBADF;
-      return -1;
-    }
-
-  result = dup2_nothrow (fd, desired_fd);
-
-  if (result == 0)
-    result = desired_fd;
-
-  return result;
-}
-
-#  define dup2 ms_windows_dup2
-
-# elif defined __KLIBC__
-
-
-static int
-klibc_dup2dirfd (int fd, int desired_fd)
-{
-  int tempfd;
-  int dupfd;
-
-  tempfd = open ("NUL", O_RDONLY);
-  if (tempfd == -1)
-    return -1;
-
-  if (tempfd == desired_fd)
-    {
-      close (tempfd);
-
-      char path[_MAX_PATH];
-      if (__libc_Back_ioFHToPath (fd, path, sizeof (path)))
-        return -1;
-
-      return open(path, O_RDONLY);
-    }
-
-  dupfd = klibc_dup2dirfd (fd, desired_fd);
-
-  close (tempfd);
-
-  return dupfd;
-}
-
-static int
-klibc_dup2 (int fd, int desired_fd)
-{
-  int dupfd;
-  struct stat sbuf;
-
-  dupfd = dup2 (fd, desired_fd);
-  if (dupfd == -1 && errno == ENOTSUP \
-      && !fstat (fd, &sbuf) && S_ISDIR (sbuf.st_mode))
-    {
-      close (desired_fd);
-
-      return klibc_dup2dirfd (fd, desired_fd);
-    }
-
-  return dupfd;
-}
-
-#  define dup2 klibc_dup2
-# endif
-
-int
-rpl_dup2 (int fd, int desired_fd)
-{
-  int result;
-
-# ifdef F_GETFL
-  /* On Linux kernels 2.6.26-2.6.29, dup2 (fd, fd) returns -EBADF.
-     On Cygwin 1.5.x, dup2 (1, 1) returns 0.
-     On Cygwin 1.7.17, dup2 (1, -1) dumps core.
-     On Cygwin 1.7.25, dup2 (1, 256) can dump core.
-     On Haiku, dup2 (fd, fd) mistakenly clears FD_CLOEXEC.  */
-#  if HAVE_SETDTABLESIZE
-  setdtablesize (desired_fd + 1);
-#  endif
-  if (desired_fd < 0)
-    fd = desired_fd;
-  if (fd == desired_fd)
-    return fcntl (fd, F_GETFL) == -1 ? -1 : fd;
-# endif
-
-  result = dup2 (fd, desired_fd);
-
-  /* Correct an errno value on FreeBSD 6.1 and Cygwin 1.5.x.  */
-  if (result == -1 && errno == EMFILE)
-    errno = EBADF;
-# if REPLACE_FCHDIR
-  if (fd != desired_fd && result != -1)
-    result = _gl_register_dup (fd, result);
-# endif
-  return result;
-}
-
-#else /* !HAVE_DUP2 */
-
-/* On older platforms, dup2 did not exist.  */
-
-# ifndef F_DUPFD
-static int
-dupfd (int fd, int desired_fd)
-{
-  int duplicated_fd = dup (fd);
-  if (duplicated_fd < 0 || duplicated_fd == desired_fd)
-    return duplicated_fd;
-  else
-    {
-      int r = dupfd (fd, desired_fd);
-      int e = errno;
-      close (duplicated_fd);
-      errno = e;
-      return r;
-    }
-}
-# endif
-
-int
-dup2 (int fd, int desired_fd)
-{
-  int result = fcntl (fd, F_GETFL) < 0 ? -1 : fd;
-  if (result == -1 || fd == desired_fd)
-    return result;
-  close (desired_fd);
-# ifdef F_DUPFD
-  result = fcntl (fd, F_DUPFD, desired_fd);
-#  if REPLACE_FCHDIR
-  if (0 <= result)
-    result = _gl_register_dup (fd, result);
-#  endif
-# else
-  result = dupfd (fd, desired_fd);
-# endif
-  if (result == -1 && (errno == EMFILE || errno == EINVAL))
-    errno = EBADF;
-  return result;
-}
-#endif /* !HAVE_DUP2 */

third_party/make/make.mk

@@ -24,7 +24,6 @@ THIRD_PARTY_MAKE_SRCS_LIB =				\
 	third_party/make/basename-lgpl.c		\
 	third_party/make/concat-filename.c		\
 	third_party/make/dirname-lgpl.c			\
-	third_party/make/dup2.c				\
 	third_party/make/error.c			\
 	third_party/make/exitfail.c			\
 	third_party/make/fcntl.c			\